Transcript

00:00:02

>> Inside a tunnel discovered under the US-Mexico border, running from a building in Tijuana, and ending in San Diego. US Border Patrol agents took Reuters underground to check it out.>> We have thus in particular the confined space entry team in there. When they discover this tunnel in there, we're the one that goes in there, assesses it, characterize it, make sure is safe for entry in there, maps it, and then gets rid of it.

00:00:26

>> According to Customs and Border Patrol, tunnels as complex as these are mostly used for drug smuggling rather than human trafficking. They can run for more than half a mile, and as deep as 90 feet below the surface.>> We have ventilation, electrical tools, rail system transport mechanisms of some sort in there.

00:00:46

That's what gives it it's sophisticated moniker. In San Diego, the average distance on these tunnels is anywhere from 1,500 all the way up to 3,000 feet.>> This particular tunnel was originally discovered back in 2013, and was filled in and shut down on the US side of the border.

00:01:05

But a few years later, Border Patrol agents discovered that the tunnel, with a few alterations, was in use again. In 2017, agents shut it down for a second time after finding about 30 people, including Mexican and Chinese nationals hiding there. But no drugs were found.